Guys, I've been using Mechanica for a long time, and while it is a very powerful tool, you need to use it with care if you want to analyse impact simulation with it. The tutorials and techniques that you see posted on the PTC web site is only good for rough appoximation, and provides some insight into how your design is going to cope with impact. For example, it will give an indication on the relative stresses at the impact point compared to other areas of the body. To try and determine failure based on the absolute stress levels is, IMHO, not going to be accurate because of the all the simplifications e.g. material linearity, strain linearity, absence of stress waves. I think even in LS-Dyna, stress waves are not taken into account. So yeah, you can use it to impress your friends and colleagues, but if you're going to present your results at peer-review meetings with other analysts, exercise caution!
